Deprecate JDK internal Catalog API in JDK 9

[Joe Wang]

Hi,

With the introduction of the new public Catalog API [1][2], we'd like to 
consider deprecating the old JDK internal API in package  
com.sun.org.apache.xml.internal.resolver and 
com.sun.org.apache.xerces.internal.util.XMLCatalogResolver. With JDK 9, 
this internal API is encapsulated (not exported), users of this API will 
shall consider migrating to the public API. The deprecation therefore is 
a further notice and also serves as an option to remove it in the future.

Your feedback on this proposal is welcome.

[1] http://openjdk.java.net/jeps/268
[2] 
http://download.java.net/java/jdk9/docs/api/javax/xml/catalog/package-summary.html

Thanks,
Joe